Teach Your Kids Mental Hygiene!
When Patri mentioned the idea of religions and cults being memetic parasites, and the following discussion bore on the difference (if any) between religions and cults, and how a same religion could sometimes have both normal and fanatical followers, my answer (in the comments) was that often the same parasite could express itself in many different ways, depending on the hygiene of the victims.
I cited the example of tape worms, that cause a rather benign intestinal infection in people having decent hygiene standards, in a way that isn't contagious to other such people, but can cause cysticercosis, a disease that will literally eat the brain of patients before it kills them, among people with low hygiene standards, in a way that is highly contagious to other such people and contagious to cleaner people as well. The hygiene standards discussed here consist in systematically washing your hands after any risk of contamination, segregating your food from your feces, avoiding meat of dubious quality, properly cooking meat that isn't known to meet high standards of quality, avoiding contact with people with poor hygiene and cleansing thoroughly after such contact.
I further argued that the very same applies in the case of those memetic parasites that religions are. I said that providing our children with proper standards of hygiene, mental as well as physical, was the most important part of parental education. It is of utmost importance that children be taught such mental hygiene rules as cleansing their minds after they've been potentially subjected to propaganda, segregating what they believe about reality from what they (and other people) fantasize, rejecting beliefs of dubious origin, thoroughly criticizing all beliefs but those that were grown using the highest standards of quality, being especially wary of people around you with low standards of mental hygiene.
I concluded: And be sure to teach that hygiene to your kids, early on. You can't change the rest of society, but you can change the people who count most around you. And once enough people adopt good hygiene, and the people with bad hygiene are weeded out by their behavior (rather than being protected or subsidized by the state), the community's standards of hygiene will get higher and the parasite will disappear, except for small ostracized fringe communities.
Now, I like to say that I don't count the word god as sacred, so I don't think religions that use it are worse than religions that don't. People who believe that the word god is special will be relaxing their mental hygiene against religions that respectively do or don't use that word, depending on these people themselves respectively believing in god or not - this is the reason why all religions, whether theistic, atheistic or neutral on this topic, tend to collaborate in spreading this belief. This meta-superstition was interestingly discussed by Mencius Moldbug (MM) on his blog devoted to debunking this memetic parasite that is the (now) atheistic religion of progressives (and their conservative hysteresical followers) who view the State as the embodiment of societal progress.
Interestingly, applying evolutionary thinking to the study of religion doesn't stop to talking about it in terms of memes. Religions evolve. They compete with each other. And where there isn't an official monopolistic religion or ideology protected by the State, religions have to compete in a ruthless struggle over believers. This yields religions that strip themselves from useless or obvious superstitions, and focus on the essential vectors of infection and payback. While there is room for plenty of variants to accommodate plenty of niches, these religions loosely converge on what MM calls the Synopsis, a lean and mean kernel of beliefs that will justify State plunder in favor of those people and institutions who will further spread same beliefs in the State.
In one of my comments to that article (you may search for Faré), I note that the very nature of the Synopsis is that it conflates the true and the false [and as another commenter further quoted from Rand, Governmental encouragement does not order men to believe that the false is true, it merely makes them indifferent to the issue of truth or falsehood.], and tries to minimize the false needed (which both makes it more fragile and makes its slaves less productive) while maximizing the return on investment of the false.
And indeed it is in freer western societies that the worst strains of statist thinking evolve into existence, out-competing other strains in their struggle for power. From there, these strains spread to less free countries, where the most efficient memes from western ideologies have massively deadly consequences on weaker populations unable to resist. Guns, germs and steel - and ideologies. In the third world, political devices are largely imported, just like all other technological devices. That's why MM is on the spot when he claims that communist regimes as well as third world dictatorships are emanations of western progressive ideological activity (the very word progressive is itself an attack vector against weak mental defenses: it takes a lot of intellectual self-assurance to dare rise against evil labelled as progress).
Happily, rational criticism, this natural defense against lies and bullshit, as promoted by infection-resistant or cured individuals is not wholly absent from the relatively free environment where these strains evolve, and this helps limit the morbidity of these pathogens, at least in western societies. But rational criticism has a cost that not everyone can afford, and the pathogens have evolved in a way that even people above average in intelligence and education can completely fail to see the edges where the web of lies falls apart. And so it's mainly the competition for more productive slaves that keeps in check the destructive effects of the Statist memes. However, this competition happens mainly between different countries rather than inside any given country, and so the political oligopoly of our world works toward increasing the level of political parasitism.
In conclusion, the biggest and most dangerous religion is Statism. It has benign and malignant modes of transmission. The best thing you can do to limit its bad effects upon you is to cultivate good mental hygiene for yourself and those you love. To avoid social disruption by epidemics of a severe form of mental infection, you may seek to spread hygiene in the society around you; failing that, your only recourse is to migrate to a society with better general standards of hygiene.